163805809 has 2 divisors, whose sum is σ = 163805810. Its totient is φ = 163805808.

The previous prime is 163805779. The next prime is 163805819. The reversal of 163805809 is 908508361.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113891584 + 49914225 = 10672^2 + 7065^2 .

It is a cyclic number.

It is not a de Polignac number, because 163805809 - 2¹³ = 163797617 is a prime.

It is not a weakly prime, because it can be changed into another prime (163805819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81902904 + 81902905.

It is an arithmetic number, because the mean of its divisors is an integer number (81902905).

Almost surely, 2^163805809 is an apocalyptic number.

It is an amenable number.

163805809 is a deficient number, since it is larger than the sum of its proper divisors (1).

163805809 is an equidigital number, since it uses as much as digits as its factorization.

163805809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 163805809 is about 12798.6643443759. The cubic root of 163805809 is about 547.1542366247.

The spelling of 163805809 in words is "one hundred sixty-three million, eight hundred five thousand, eight hundred nine".